Résistance aux antibiotiques de Staphylococcus aureus isolé des infections communautaires et hospitalières à Casablanca

The global prevalence of fusidic acid resistance in clinical isolates of Staphylococcus aureus: a systematic review and meta-analysis

BACKGROUND AND AIM

Staphylococcus aureus (S. aureus) is one of the most common pathogens causing nosocomial and community-acquired infections with high morbidity and mortality rates. Fusidic acid has been increasingly used for the treatment of infections due to methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). The present study aimed to determine the precise prevalence of fusidic acid resistant MRSA (FRMRSA), fusidic acid resistant MSSA (FRMSSA), and total fusidic acid resistant S. aureus (FRSA) on a global scale.

METHODS

Several international databases including Medline, Embase, and the Web of Sciences were searched (2000-2020) to discern studies addressing the prevalence of FRSA, FRMRSA, and FRMSSA. STATA (version14) software was used to interpret the data.

RESULTS

Of the 1446 records identified from the databases, 215 studies fulfilled the eligibility criteria for the detection of FRSA (208 studies), FRMRSA (143 studies), and FRMSSA (71 studies). The analyses manifested that the global prevalence of FRSA, FRMRSA, and FRMSSA was 0.5%, 2.6% and 6.7%, respectively.

CONCLUSION

This meta-analysis describes an increasing incidence of FRSA, FRMSSA, and FRMRSA. These results indicate the need for prudent prescription of fusidic acid to stop or diminish the incidence of fusidic acid resistance as well as the development of strategies for monitoring the efficacy of fusidic acid use.

Mass spectrometry and multiplex antigen assays to assess microbial quality and toxin production of Staphylococcus aureus strains isolated from clinical and food samples

The aim of our study was to investigate the microbial quality of meat products and on some clinical samples in Abidjan focused on Staphylococcus genus and the toxin production profile of Staphylococcus aureus (S. aureus) isolated. Bacteria were collected from 240 samples of three meat products sold in Abidjan and 180 samples issued from clinical infections. The strains were identified by both microbiological and MALDI-TOF-MS methods. The susceptibility to antibiotics was determined by the disc diffusion method. The production of Panton-Valentine Leukocidin, LukE/D, and epidermolysins was screened using radial gel immunodiffusion. The production of staphylococcal enterotoxins and TSST-1 was screened by a Bio-Plex Assay. We observed that 96/240 of meat samples and 32/180 of clinical samples were contaminated by Staphylococcus. Eleven species were isolated from meats and 4 from clinical samples. Forty-two S. aureus strains were isolated from ours samples. Variability of resistance was observed for most of the tested antibiotics but none of the strains displays a resistance to imipenem and quinolones. We observed that 89% of clinical S. aureus were resistant to methicillin against 58% for those issued from meat products. All S. aureus isolates issued from meat products produce epidermolysins whereas none of the clinical strains produced these toxins. The enterotoxins were variably produced by both clinical and meat product samples.

Variability of antibiotic susceptibility and toxin production of Staphylococcus aureus strains isolated from skin, soft tissue, and bone related infections

Background

Staphylococcus aureus is an opportunistic commensal bacterium that mostly colonizes the skin and soft tissues. The pathogenicity of S. aureus is due to both its ability to resist antibiotics, and the production of toxins. Here, we characterize a group of genes responsible for toxin production and antibiotic resistance of S. aureus strains isolated from skin, soft tissue, and bone related infections.

Results

A total of 136 S. aureus strains were collected from five different types of infection: furuncles, pyomyositis, abscesses, Buruli ulcers, and osteomyelitis, from hospital admissions and out-patients in Benin. All strains were resistant to benzyl penicillin, while 25% were resistant to methicillin, and all showed sensitivity to vancomycin. Panton-Valentine leukocidin (PVL) was the most commonly produced virulence factor (70%), followed by staphylococcal enterotoxin B (44%). Exfoliative toxin B was produced by 1.3% of the strains, and was only found in isolates from Buruli ulcers. The tsst-1, sec, and seh genes were rarely detected (≤1%).

Conclusions

This study provides new insight into the prevalence of toxin and antibiotic resistance genes in S. aureus strains responsible for skin, soft tissue, and bone infections. Our results showed that PVL was strongly associated with pyomyositis and osteomyelitis, and that there is a high prevalence of PVL-MRSA skin infections in Benin.

Emergence of vancomycin-resistant Staphylococcus aureus identified in the Tlemcen university hospital (North-West Algeria)

INTRODUCTION

Nosocomial infections are a matter of concern in surgical wards. Their incidence is constantly increasing, especially among immunocompromised patients who are vulnerable to colonization by opportunistic pathogens such as Staphylococcus aureus. The bacterium accumulates resistance mechanisms against antibiotics such as vancomycin. The objective of our study was to explore this resistance, to screen for Staphylococcus aureus strains resistant to vancomycin, and to try various antibiotic combinations against these strains.

PATIENTS AND METHODS

The antibiotic susceptibility of 220 S. aureus strains was determined by agar diffusion and evaluation of minimal inhibitory concentrations (MICs), by dilution technique on solid medium according to clinical and laboratory standard institute (CLSI) standards. The screening of strains resistant to vancomycin was performed on brain heart infusion agar medium, supplemented with 6μg/mL of vancomycin according to CLSI standards, and confirmed by determining MICs. The effectiveness of various antibiotic combinations was assessed by the checkerboard microplate method.

RESULTS

The results show multidrug resistance to agents known for their antistaphylococcal activity with fluctuations in the level of resistance.

CONCLUSION

Three strains proved resistant to vancomycin. The vancomycin/gentamycin combination was the most effective.

Multicenter pilot survey of resistant bacteria in the Mediterranean area

With the aim of testing the feasibility of a multiresistant bacteria (MRB) surveillance methodology and evaluating the level of antimicrobial resistance and dissemination of resistant pathogens in the Mediterranean area, a pilot study was carried out in nine university hospitals in Algeria, Tunisia and France. The results indicate that third-generation cephalosporin-resistant Enterobacteriaceae comprise the major MRB in Algerian and Tunisian hospitals. In France, the highest incidence rates were found for methicillin-resistant Staphylococcus aureus, while in Tunisian hospitals, imipenem-resistant Acinetobacter baumannii seems to be a particularly prevalent organism. Although the data were not representative of the participating countries as a whole, the results show the importance and ubiquity of the problem in the area and the feasibility of surveillance.

Place des bactériémies à Staphylococcus aureus au CHU de Fann à Dakar

OBJECTIVES

The purpose of this report was to describe epidemiological, clinical, and bacteriological findings in cases of Staphylococcus aureus bacteremia at the Infectious Diseases Clinic in Dakar.

MATERIALS AND METHODS

This retrospective study was carried out on data recorded between January 1, 1996 and December 31, 2002. The diagnosis of bacteremia was based on isolation of bacteria from blood culture. Bacterial susceptibility was studied with an antibiogram. Resistance to methicillin was assessed with a disk containing 5 microg of oxacillin on Mueller Hinton Agar containing 5% of NaCl.

RESULTS

One hundred and thirty cases of S. aureus bacteremia were recorded. The mean age of patients was 31 years. Nosocomial bacteremia occurred in 22% of the cases. HIV infection was noted in 38 patients (29%). The death rate was 24%. Nosocomial and community-acquired strains were resistant to methicillin, respectively, in 72% and 51% of the cases. Bacteremias due to methicillin-resistant S. aureus strain were nosocomial infections in 23% of the cases. Most of the strains (80-100%) were susceptible to fusidic acid, gentamycin, erythromycin, and pefloxacin. All of them were susceptible to vancomycin.

CONCLUSION

Such a high rate of MRSA bacteremia, in particular among nosocomial bacteremia, makes it essential to reinforce preventive measures in our hospitals and to provide them with effective drugs against MRSA, such as vancomycin.

[Antibiotic resistance of Staphylococcus aureus at north Lebanon: place of the methicillin resistance and comparison of detection methods]

The aim of this study was to evaluate the susceptibility of 100 Staphylococcus aureus strains isolated from the laboratory of Microbiology of the Islami Hospital of Tripoli (Lebanon) to 19 antibiotics, and to determine the prevalence of methicillin resistant strains. 30% of strains studied were methicillin resistant, 96% were resistant to the penicillin G. Clavulanic acid restaurated the amoxicillin activity to 29%. The resistance level was 34% for amikacin, 3% for gentamycin and tobramycin, 10% for chloramphenicol, 44.33% for tetracyclin, 7% for erythromycin, 4.04% for clindamycin, 20% for trimethoprim-sulfametoxasol and 0% for vancomycin and teicoplanin. The methicillin-resistant Staphylococcus aureus possess more important resistant level in comparison with the methicillin sensitive strains. We compared the ability of latex agglutination test (Slidex(R) SARM, bioMérieux, France) to detect the production of penicillin-binding protein 2' (PBP 2') in 100 clinical isolates of S. aureus with two reference methods: the oxacillin disk diffusion test and the MIC determination by the E-test (AB BIODISK, Sweden). The two reference methods give the same results for the detection of methicillin resistant S. aureus. The Slidex test was positive for all 30 isolates determined to be methicillin resistant by the reference methods (sensitivity 100%). The latex test was negative for 42 of 70 isolates determined to be methicillin susceptible by the reference methods, and the latex test was positive for 28 isolates determined to be susceptible (specificity 60%).